SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb208d45ea5b167c17aa1b60b390cdcac19ef67110668f6296d3fba55d19a7d6' 
  AND token = 'eakCbeD4/relbrekS9OUQRwGnq2WOpii3TEXJOvcAuM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}